What Is the Definition of “Competence” in Intracranial Aneurysm Surgery in the Endovascular Era of Aneurysm Management? Back to the Future

Introduction: In the ISAT study, an arbitrary minimum of 30 aneurysm coiling procedures was necessary to qualify an interventional neuroradiologist to participate in the clinical trial. No specific experiential criteria were defined for neurosurgeons. At what point in time or with what aggregate volume of experience is a neurosurgeon deemed to be “competent” in intracranial aneurysm surgery, particularly in the current endovascular era, with declining surgical aneurysm cases? How competent is a new neurosurgeon after independently treating an initial 30 aneurysms in the initial phase of neurosurgical practice experience?

Methods:(1) A comprehensive review was conducted of the first year of independent practice/first 30 independently performed aneurysm clippings for a single cerebrovascular/skull base fellowship-trained neurosurgeon, who is currently in his 10th year of neurosurgical practice experience. (2) Data were reviewed for patient age, clinical grade, initial surgical outcome, and 3-month outcome. (3) Surgical cases were reviewed to determine if training and/or experience influenced complications and/or outcome. (4) Data are reported in the aggregate.

Results: Median patient age was 52 years. More than half (57%) of the cases in this series were considered severe bleeds (Fisher grades III and III + IV). Anterior communicating artery aneurysms were most common (40%). Large/giant aneurysms were found in 4 of 30 cases (13.3%), with the following measurements: 21 mm, 26 mm, and 30 mm. In 93.3% of the cases, the Glasgow Outcome Score was 4 or 5 (80% GOS 5, 13.3% GOS 4). There was no statistically significant difference between the clinical grade of the first 15 cases compared with the second 15 cases in this series (P = 0.80). Experience did affect complication rates when comparing the first 15 cases to the second 15 cases (P = 0.03). A decreasing incidence of complications, defined as “experienced-related,” was seen over time—all complications occurred in the first 15 cases for this practitioner.

Conclusions: The notion of acceptable levels of competence in intracranial aneurysm surgery is nebulous and rests on dynamic definitions of what constitutes good technical expertise and sufficient cognitive background, as well as, to a significant extent, on internecine ego clashes within the neurosurgical specialty. The complexity of any given surgical case can always increase as the length of time in neurosurgical practice increases. However, the bedrock of fundamental skills and knowledge essential to successful aneurysm surgery is still based in neurosurgery residency/fellowship training and perhaps, more importantly, in certain innate tendencies of the individual. In an era of decreasing absolute volumes of surgical aneurysm cases and increasing technical complexity of aneurysms referred for microsurgery, further active discussion regarding issues of competence in intracranial aneurysm surgery merits the continued sincere attention of neurosurgical educators. Issues of competence in aneurysm surgery have important clinical and educational implications in the overall organization and delivery of subspecialty neurosurgical care in an ever-changing health care environment in the United States and beyond.